Got the solution from here: Shut down the guest machine Select the Ubuntu 14.04 virtual machine and click the Settings button Select the ‘Display’ item from the list on the left In the Video tab on the right, check the ‘Enable 3D Video Acceleration’ option Select the ‘Storage’ item from the list on the left …

Assuming your Ubuntu guest username is USERNAME: Make sure you have already installed the VirtualBox Guest Additions in the Ubuntu guest machine From the Ubuntu guest: sudo adduser USERNAME vboxsf Using the VirtualBox UI (Devices->Shared Folder Settings…) add the folder in the hosting machine that you wish to share. Restart the Ubuntu guest! (wasted too …